730 d. white late theories regarding the origin of oil 



Distillation versus Bacterial Origin 



However, as to the actual mode of origin of oil from plant and animaJ 

 matter, there are, besides many minor differences of opinion touching one 

 point or another, two divergent views of primary rank. The first view, 

 with which all are familiar, is that supported by Newberry and Orton, 

 but really centuries old, that petroleum is generated by natural earth 

 processes more or less similar in effect to the distillation, under geother- 

 mal and dynamic influences, of the organic matter buried in the sedi- 

 ments. The other view is that the oil is generated through the action of 

 anaerobic bacteria working in the putrifying debris as it is buried in the 

 muds — at the time of or very soon after deposition of the organic debris. 



The importance of microbes, particularly anaerobic bacteria, in the 

 transformation of the organic com]30unds in the debris as it accumulates 

 and becomes buried in the strata was clearly demonstrated with almost 

 marvelous microscopical technique by Eenault and Bertrand. This work 

 of the micro-organisms affects both the accumulating debris, composed 

 mainly of vascular plants and destined to form coals, and that composing 

 the mother debris of petroleum, whether this debris be scattered in the 

 muds of future shales, impure limestones, etcetera, or accumulated in 

 relative purity to form future cannels and bogheads. This initial putre- 

 faction process, the bacterial decomposition of the organic debris, I have 

 for emphasis distinguished as the hio chemical process, or the hiochemical 

 stage, in contradistinction to those chemical changes which are later in- 

 duced in the buried organic deposits through dynamic or other influences 

 of purely geologic origin, and which are, on the other hand, dynamo- 

 chemical, or, to use a better word, geochemical. According to my view, 

 the activity of the bacteria probably ceases before the organic deposits are 

 buried to a great depth or have been subjected to any considerable dehy- 

 dration, lithification, and progressive devolatilization. But it was Ee- 

 nault's belief that in the case of coals the rank of the coal, such as lignite, 

 bituminous, or anthracite, was dependent solely on the kinds and the 

 duration of the microbian action. 



I am not aware that Renault ever applied his theory specifically to 

 petroleum, though such an application is suggested in his discussions. 

 The formal elaboration of the biochemical hypothesis of the origin of 

 petroleum, making the oil a direct product of the putrefaction of the 

 organic debris, seems to rest mainly on the observations noted by Sicken- 

 burger,^2 Eedwood,^^ and A. B. Thompson,^* which include the occur- 



12 Chem.-Zeit., vol. 15, 1891, p. 1582. 



13 Petroleum, 3d ed., vol. 1, pp. 132-148. 

 "Oil-field development, 1916, p. 270. 



